SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4d6232749394564f74b45e08672f08a0a72166fbcc17daf32f24af924b611b0' 
  AND token = 'xIuqKXgzUnnr3CJ43RNl5tsYI5Gy+2P801SIc6kBGM0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}